Methods of manufacture and use of endoluminal devices

ABSTRACT

A seamless, self-expanding implantable device having a low profile is disclosed along with methods of making and using the same. The implantable device includes a frame cut out of a single piece of material that is formed into a three-dimensional shape. The implantable device may comprise an embolic filter, stent, or other implantable structure. The present invention also allows complicated frame structures to be easily formed from planar sheets of starting material, such as through laser cutting, stamping, photo-etching, or other cutting techniques.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Division of U.S. patent application Ser. No.10/113,724 filed Apr. 1, 2002.

FIELD OF THE INVENTION

The present invention relates to seamless endoluminal devices includingframe patterns for filters, their manufacture and use in the filtrationand/or removal of embolic matter from fluids flowing in tubular bodylumens including, but not limited to: blood flow in arteries and veins;airflow within the respiratory tract; and the flow of urine in theurinary tract. The seamless filter of the present invention may beself-expanding, is deployable via a guidewire-based system and has a lowprofile.

BACKGROUND OF THE INVENTION

Embolic protection is a concept of growing clinical importance directedat reducing the risk of embolic complications associated withinterventional (i.e., transcatheter) and surgical procedures. Intherapeutic vascular procedures, liberation of embolic debris (e.g.,thrombus, clot, atheromatous plaque, etc.) can obstruct perfusion of thedownstream vasculature, resulting in cellular ischemia and/or death. Thetherapeutic vascular procedures most commonly associated with adverseembolic complications include: carotid angioplasty with or withoutadjunctive stent placement and revascularization of degeneratedsaphenous vein grafts. Additionally, percutaneous transluminal coronaryangioplasty (PTCA) with or without adjunctive stent placement, surgicalcoronary artery by-pass grafting, percutaneous renal arteryrevascularization, and endovascular aortic aneurysm repair have alsobeen associated with complications attributable to atheromatousembolization. Intra-operative capture and removal of embolic debris,consequently, may improve patient outcomes by reducing the incidence ofembolic complications.

The treatment of stenoses of the carotid bifurcation provides a goodexample of the emerging role of adjuvant embolic protection.Cerebrovascular stroke is a principle source of disability among adults,and is typically associated with stenoses of the carotid bifurcation.The current incidence of cerebrovascular stroke in Europe and the UnitedStates is about 200 per 100,000 population per annum (Bamford,Oxfordshire community stroke project Incidence of stroke in Oxfordshire.First year's experience of a community stroke register. BMJ 287:713-717, 1983; Robins, The national survey of stroke: the NationalInstitute of Neurological and Communicative Disorders and Stroke. Officeof Biometry and Field Studies Report. Chapter 4. Incidence. Stroke 12(Suppl. 1): 1-57, 1981). Approximately half of the patients sufferingischemic stroke have carotid artery stenoses (Hankey, Investigation andimaging strategies in acute stroke and TIAs. Hospital Update 107-124,1992). Controlled studies have shown that the surgical procedure carotidendarterectomy (CEA) can reduce the incidence of stroke in patientscompared to medical therapy with minimal perioperative complications(<6% for symptomatic patients with stenoses >70% [NASCET, Beneficialeffect of carotid endarterectomy in symptomatic patients with high gradestenoses. NEJM 325:445-453, 1991] and <3% for asymptomatic patients with60% stenoses [ACAS, Endarterectomy for asymptomatic carotid arterystenosis. JAMA 273: 1321-1461, 1995]). These results provide convincingevidence of the benefit of treating carotid stenoses. Surgery, however,does have several limitations, including: increased mortality inpatients with significant coronary disease (18%), restriction to thecervical portion of the extra-cranial vasculature, a predeliction forcranial palsies (7.6%-27%), and restenosis (5%-19%; Yadav, Electivestenting of the extracranial carotid arteries. Circulation 95: 376-381,1997).

Carotid angioplasty and stenting have been advocated as potentialalternatives to CEA. Percutaneous techniques have the potential to beless traumatic, less expensive, viable in the non-cervical extracranialvasculature, and amenable to patients whom might otherwise be inoperable(Yadav, Elective stenting of the extracranial carotid arteries.Circulation 95: 376-381, 1997). Despite the potential benefits of thisapproach, emboli liberated during trans-catheter carotid interventioncan place the patient at risk of stroke. Emboli can be generated duringinitial accessing of the lesion, balloon pre-dilatation of the stenosis,and/or during stent deployment. Additionally, prolapse of atheromatousmaterial through the interstices of the stent can embolize after thecompletion of the procedure.

The fear of dislodging an embolus from an atherosclerotic plaque hastempered the application of angioplasty and endovascular stenting to thesupraaortic arteries and, particularly, to the carotid bifurcation(Theron, New triple coaxial catheter system for carotid angioplasty withcerebral protection. AJNR 11: 869-874, 1990). This concern is warranteddue to the significant morbidity and/or mortality that such an eventmight produce. While the incidence of stroke may be at an acceptablelevel for the highly skilled practitioner, it is likely to increase asthe procedure is performed by less experienced clinicians.

Embolic protection devices typically act as an intervening barrierbetween the source of the clot or plaque and the downstream vasculature.In order to address the issue of distal embolization, numerous apparatushave been developed and numerous methods of embolic protection have beenused adjunctively with percutaneous interventional procedures. Thesetechniques, although varied, have a number of desirable featuresincluding: intraluminal delivery, flexibility, trackability, smalldelivery profile to allow crossing of stenotic lesions, dimensionalcompatibility with conventional interventional implements, ability tominimize flow perturbations, thromboresistance, conformability of thebarrier to the entire luminal cross-section (even if irregular), and ameans of safely removing the embolic filter and trapped particulates.

For example, occlusion balloon techniques have been taught by the priorart and involve devices in which blood flow to the vasculature distal tothe lesion is blocked by the inflation of an occlusive balloonpositioned downstream to the site of intervention. Following therapy,the intraluminal compartment between the lesion site and the occlusionballoon is aspirated to evacuate any thrombus or atheromatous debristhat may have been liberated during the interventional procedure. Thesetechniques are described in Theron, New triple coaxial catheter systemfor carotid angioplasty with cerebral protection. AJNR 11: 869-874,1990, and Theron, Carotid artery stenosis: Treatment with protectedballoon angioplasty and stent placement. Radiology 201:627-636, 1996,and are commercially embodied in the PercuSurge Guardwire Plus™Temporary Occlusion and Aspiration System (Medtronic AVE). The principledrawback of occlusion balloon techniques stem from the fact that duringactuation distal blood flow is completely inhibited, which can result inischemic pain, distal stasis/thrombosis, and difficulties withfluoroscopic visualization due to contrast wash-out through the treatedvascular segment.

Another prior system combines a therapeutic catheter (e.g., angioplastyballoon) and integral distal embolic filter. By incorporating a porousfilter or embolus barrier at the distal end of a catheter, such as anangioplasty balloon catheter, particulates dislodged during aninterventional procedure can be trapped and removed by the sametherapeutic device responsible for the embolization. One known deviceincludes a collapsible filter device positioned distal to a dilatingballoon on the end of the balloon catheter. The filter comprises aplurality of resilient ribs secured to the circumference of the catheterthat extend axially toward the dilating balloon. Filter material issecured to and between the ribs. The filter deploys as a filter balloonis inflated to form a cup-shaped trap. The filter, however, does notnecessarily seal around the interior vessel wall. Thus, particles canpass between the filter and the vessel wall. The device also presents alarge profile during positioning and is difficult to construct.

The prior art has also provided systems that combine a guidewire and anembolic filter. The filters are incorporated directly into the distalend of a guidewire system for intravascular blood filtration. Given thecurrent trends in both surgical and interventional practice, thesedevices are potentially the most versatile in their potentialapplications. These systems are typified by a filter frame that isattached to a guidewire that mechanically supports a porous filterelement. The filter frame may include radially oriented struts, one ormore circular hoops, or a pre-shaped basket configuration that deploysin the vessel. The filter element typically includes a polymeric meshnet, which is attached in whole or in part to the filter frame and/orguidewire. In operation, blood flowing through the vessel is forcedthrough the mesh filter element thereby capturing embolic material inthe filter.

Early devices of this type include a removable intravascular filtermounted on a hollow guidewire for entrapping and retaining emboli. Thefilter is deployable by manipulation of an actuating wire that extendsfrom the filter into and through the hollow tube and out the proximalend. During positioning within a vessel, the filter material is notfully constrained so that, as the device is positioned through and pasta clot, the filter material can potentially snag clot material creatingfreely floating emboli, prior to deployment.

In another prior art system an emboli capture device is mounted on thedistal end of a guidewire. The filter material is coupled to a distalportion of the guidewire and is expanded across the lumen of a vessel bya fluid activated expandable member in communication with a lumenrunning the length of the guidewire. During positioning, as the deviceis passed through and beyond the clot, filter material may interact withthe clot to produce emboli. This device may also be difficult tomanufacture.

Another prior art device is adapted for deployment in a body vessel forcollecting floating debris and emboli in a filter that includes acollapsible proximally tapered frame for operably supporting the filterbetween a collapsed insertion profile and an expanded deploymentprofile. The tapered collapsible frame includes a mouth that is sized toextend to the walls of the body vessel in the expanded deployed profileto seal the filter relative to the body vessel for collecting debrisfloating in the body vessel.

A further example of an embolic filter system involves a filter materialfixed to cables or spines of a central guidewire. A movable core orfibers inside the guidewire can be utilized to transition the cables orspines from approximately parallel to the guidewire to approximatelyperpendicular to the guidewire. The filter, however, may not seal aroundthe interior vessel wall. Thus, particles can pass between the filterand the entire vessel wall. This umbrella-type device is shallow whendeployed so that, as it is being closed for removal, particles have thepotential to escape.

Other disadvantages associated with the predicate devices are that thesteerability of the guidewire may be altered as compared to theconventional guidewires due to the presence and size of the filter. Theguidewire, for example, may bend, kink, and/or loop around in thevessel, making insertion of the filter through a complex vascular lesiondifficult. Also, delivery of such devices in a low-profilepre-deployment configuration can be difficult. Further, some devicesinclude complex and cumbersome actuation mechanisms. Also, retrievingsuch capture devices after they have captured emboli may be difficult.Further, when deployed in curved segments, the interaction of theguidewire and/or tether elements can deform the filter frame in such away as to limit apposition to the host vessel wall, thereby allowingpotential channels for passage of embolic debris. Also, the filter mediaof the prior art maintains a pore diameter of approximately 80 to 120microns. It is desirable to minimize the pore size without adverselyperturbing blood flow or being prone to clogging.

Current filter designs suffer from numerous disadvantages due to theirconstruction. A typical wire filter is formed by manipulating multiplewires together through welding or some other form of attachment. Afterthe wire frame is constructed, it is formed into the desired shape and afilter element is affixed onto the wire cage. A typical wire frameconstructed in this manner is subject to a limited range of manipulationafter the wires are adhered, since the welds or attachment areas are atan increased risk of failure due to the physical constraints of thewelds themselves. A wire pair is more inclined to fracture at theweakest point, typically, a wire frame, composed of numerous wire pairs,will separate at the weld before separating in the length of the wire.Additionally, the welding of metal involves the application of increasedheat to join a wire pair and a risk exists of the mesh, formed by thepairs, dripping or otherwise malforming due to the proclivity of metalto run before cooling.

A further disadvantage to a typical wire filter is that the filterelement is difficult to apply to the frame since the filter is normallyapplied as a sock, tube, or other such shape. The typical wire frame isformed by welding and bending into the desired shape. The filter is thenaffixed onto the shaped wire frame by pulling the formed filter over theshaped wire frame. An additional problem evident in this construction isthat the filter element could be abraded by a protrusion formed by aweld in a wire pair. Such an abrasion could form a weakness or a tear inthe filter and undermine its desired functionality.

Simple and safe blood filtering and guidewire systems that can betemporarily placed in the vasculature to prevent distal embolizationduring endovascular procedures, and that can be used to introduce and/orexchange various instruments to a region of interest withoutcompromising the position of the filter or guidewire, are required.Existing guidewire-based embolic filtering devices are inadequate forthese and other purposes. The present apparatus, in contrast, provides anovel means of providing these and other functions, and has the furtherbenefit of being easier to manufacture than the devices of the priorart.

SUMMARY OF THE INVENTION

The present invention relates to seamless implantable devices, filters,methods of manufacture, systems for deployment and methods of use.

One aspect of the present invention is to provide a low profile filterformed from a single piece of material.

Another aspect of the present invention is to provide a self-expandingfilter that is seamless.

A further aspect of the present invention is to provide an integralself-expanding filter frame that is seamless.

A still further object of the present invention is to provide aseamless, low-profile filter that minimally perturbs flow.

A further aspect of the present invention to provide a low profile,seamless filter that is readily connected to the guidewire of aendoluminal deployment system.

A further aspect of the invention is to provide a filter apparatus,which maintains vessel wall apposition and a maximally open mouth whendeployed in tortuous anatomy.

A further aspect of the invention is to provide a filter frame, whichcan be rendered sufficiently radiopaque.

A further aspect of the present invention is to provide filters whichhave increased capture efficiency and are capable of providing drugdelivery.

A further aspect according to the present invention includes providing aseamless frame having a proximal end, a longitudinal axis, a seamlesssupport member circumscribing the axis and distally spaced from theproximal end, and at least one attachment strut, and optionally at leastone filter strut seamlessly extending from the support member.

Another aspect of the present invention is to provide a seamless framehaving a proximal end, a longitudinal axis, a seamless support membercircumscribing the axis and distally spaced from the proximal end, andat least one attachment strut, optionally at least one filter strutseamlessly extending from the support member, and at least one or morefilter media layers.

Another aspect of the present invention is to provide implantabledevices that may be configured as detachable devices designed forpermanent implantation and/or subsequent retrieval and are used for:temporary vascular occluders; exclusion of bleeding varices oraneurysmal vascular segments; a stent, or similar means of providingstructural support to an endoluminal cavity; a thrombectomy/atherectomyinstrument; an implantable prosthetic vascular conduit wherein theproximal filter frame functions as an anchoring stent, and the distalfilter is configured into an open-ended, tubular configuration (similarto a windsock) allowing endoluminal lining of a vascular segment with abiocompatible liner.

An aspect of the present invention is to provide seamless implantabledevices formed from a single piece of material.

Another aspect of the present invention is to provide seamlessimplantable devices that have regions of articulation and/or radiopaquemarkers.

A further aspect of the present invention to provide seamlessimplantable devices that include radiopaque markers.

A still further aspect of the present invention is to provide stents orsimilar means of providing structural support to an endoluminal cavity,and which may include regions of articulation and/or radiopaque markers.

A further aspect of the present invention to provide a seamless stent,or similar means of providing structural support to an endoluminalcavity.

A still further aspect of the present invention is to provide a deliverysystem for the inventive seamless devices, stents, occluders, filtersand its use. These and other features and aspects of the invention willbecome more apparent in view of the following detailed description,non-limiting examples, appended claims and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A, 1B and 1C illustrate the steps of constructing a firsttwo-dimensional frame, whereas FIGS. 1D and 1E illustrate a resultingthree-dimensional shape with a filter media attached thereto.

FIGS. 2A, 2B and 2C respectively illustrate an alternate configurationof a two-dimensional frame, a resulting three-dimensional shape afterannealing and a depiction of the frame with a filter media attached.

FIGS. 3A, 3B and 3C respectively illustrate an alternate configurationof a two-dimensional frame, a resulting three-dimensional shape afterannealing and a depiction of the frame with a filter media attached.

FIGS. 4A, 4B and 4C respectively illustrate an alternate configurationof a two-dimensional frame, a resulting three-dimensional shape afterannealing and a depiction of the frame with a filter media attached.

FIGS. 5A, 5B and 5C respectively illustrate an alternate configurationof a two-dimensional frame, a resulting three-dimensional shape afterannealing and a depiction of the frame with a filter media attached.

FIGS. 6A, 6B and 6C respectively illustrate an alternate configurationof a two-dimensional frame, a resulting three-dimensional shape afterannealing and a depiction of the frame with a filter media attached.

FIGS. 7A, 7B and 7C respectively illustrate an alternate configurationof a two-dimensional frame, a resulting three-dimensional shape afterannealing and a depiction of the frame with a filter media attached.

FIG. 7D illustrates an annealed frame pattern having articulationsegments in the attachment struts and FIG. 7E illustrates a framepattern having longitudinally spaced support members interconnected byarticulation segments.

FIGS. 8A, 8B and 8C respectively illustrate an alternate configurationof a two-dimensional frame, a resulting three-dimensional shape afterannealing and a depiction of the frame with a filter media attached.

FIGS. 9A, 9B and 9C respectively illustrate an alternate configurationof a two-dimensional frame, a resulting three-dimensional shape afterannealing and a depiction of the frame with a filter media attached.

FIGS. 10A, 10B and 10C respectively illustrate an alternateconfiguration of a two-dimensional frame, a resulting three-dimensionalshape after annealing and a depiction of the frame with an integralfilter media.

FIGS. 11A, 11B and 11C respectively illustrate an alternateconfiguration of a two-dimensional frame, a resulting three-dimensionalshape after annealing and a depiction of the frame with a filter mediaattached.

FIGS. 12A, 12B, 12C, 12D and 12E respectively illustrate alternate apexand strut configurations adapted to accept and house radio-opaquemarkers.

FIG. 13 illustrates a three-dimensional frame with an attached filtermedia positioned between a guidewire and an atraumatic tip.

FIGS. 14A and 14B depict the filtering apparatus as deployed within avessel having tortuous anatomy.

FIG. 15 illustrates an alternate system for assembling an alternateembolic filter configuration.

FIG. 16 illustrates a system for assembling a filter-in-filter device.

FIG. 17 illustrates the filter-in-filter assembled using the system ofFIG. 16.

FIGS. 18A, 18B and 18C respectively illustrate a tooling device, atwo-dimensional frame being formed into a three-dimensionalconfiguration, and the tooling device supporting the three-dimensionalframe for annealing.

FIGS. 19A, 19 B and 19C respectively illustrate the steps for convertinga conical filter into “sombrero” shaped filter configuration.

FIG. 19D illustrates a three-dimensional frame supporting a “sombrero”shaped filter media.

FIGS. 19 E and 19F depict an alternative filter sack configuration inwhich the sack resembles an asymmetric cone.

FIGS. 20A, 20B and 20C respectively illustrate a filter-in-filterconfiguration with a pharmacological agent loaded in the space betweenthe filter media, an alternate filter configuration with the filtermedia pre-loaded with the pharmacological agent, and the elution of thepharmacological agent in a lumen/vessel of a host.

FIGS. 21A and 21B respectively illustrate deployment of an occluderdevice in a lumen/vessel of a host and the detachment of the occluder.

FIGS. 22A and 22B respectively illustrate the deployment of anobstruction remover and collection of removed lesion debris in alumen/vessel of a host.

FIGS. 23A, 23B and 23C illustrate the use of an anchoring device fortreatment of a lesion in tortuous vessels associated with renal anatomy.

FIGS. 24A, 24B, 24C, 24D and 24E respectively illustrate a twodimensional frame, a three-dimensional resulting shape, an endovasculardevice formed from the three-dimensional frame and an open-endedwindsock, the occlusion of a sacular aneurysm in a host lumen/vesselwith the endovascular device and optional use of a stent lining thedevice.

FIG. 25A illustrates a delivery catheter having a guidewire lumen andguidewire supported filter.

FIGS. 25B, 25C, 25D and 25E respectively illustrate views of alternatedistal catheter delivery tips.

FIGS. 25F, 25G and 25H respectively illustrate three-dimensional topviews of catheter tube having a channel indented in its surface adjacentits distal end, a sleeve covering the indented channel and a guidewirelocated in the sleeve covered-indented channel.

FIGS. 26A, 26B, 26C 26D and 26E respectively illustrate steps followedin treating a lesion in a host lumen/vessel.

FIGS. 27A, 27B and 27C respectively illustrate a view of the distal tipa delivery catheter with an alternate auxiliary lumen configuration, athree-dimensional top view of the auxiliary lumen configuration and anauxiliary lumen mounted guidewire.

FIG. 28 illustrates a configuration of the present invention deployed asan implantable vena cava filter.

FIGS. 29A and 29B respectively illustrate an alternate two-dimensionalplanar configuration of the present invention, and a three-quarterisometric view of this configuration formed into a three-dimensionalshape designed for use as an implantable stent.

FIG. 30 is a flat pattern view of a filter frame and integral tetherelements as would be cut from a tube.

FIG. 31 is a flat pattern view of a filter frame and integral tetherelements after being formed and annealed at a functional size.

FIGS. 32A, 32B, 32C, 32D and 32E respectively show variations in thetether geometry, designed to allow the tethers to articulate withrespect to one another and to the filter frame itself.

DETAILED DESCRIPTION OF THE INVENTION

As used herein the following terms are defined as followed:

The term “proximal” is defined as the location closest to the catheterhub and “distal” is the location most distant from the catheter hub.With respect to the inventive three-dimensional uni-body frame, the term“proximal” is the frame end attached to the guidewire or the frame sidethrough which debris enters to be collected by an associated filter.

The term “uni-body” refers to a frame pattern formed from a single pieceof material and therefore considered “seamless.”

Terms such as unitary, integral, one-piece are synonymous with“uni-body” and also refer to a frame pattern that is formed from asingle or common piece of material.

Filament, wire or ribbon are alternate terms used to describe theportions/sections of pattern material that remain after etching a planarprecursor frame material and form the attachment struts, the supportstruts, the filter/filter support struts that extend in thelongitudinal, circumferential, or any other direction necessary todefine a frame pattern.

FIGS. 1A-1D schematically show the four method steps that are followedto manufacture a uni-body, self-expanding filter device in accordancewith the present invention. FIG. 1A shows a flat sheet material 110,preferably a shape memory alloy material, e.g., a NiTi alloy, Nitinol,or any other suitable bioacceptable material, such as a metal, e.g.,stainless steel, or bioacceptable polymer. The flat sheet material 110is used to form the “uni-body” frame pattern 115 of FIG. 1C, or otherframe patterns described hereinafter.

A desired pattern is formed on sheet material 110, as in the case ofFIG. 1B, which shows a radially symmetric filter frame pattern havingsix “pie” shaped wedges 120. The wedges 120 are removed by etching in achemical photo-etching process, or any other suitable technique, to forma frame defined by filament sized material. The frame pattern can alsobe obtained by using a laser or any other cutting procedure or processcapable of precisely etching, stamping, or otherwise cutting the flatsheet 110 into the preferred shape.

Radial sides 125, 130 and arcuate side 135 circumscribe the wedges 120.Slits 145 are formed and center section 150 is removed by any suitablecutting technique. After the slits 145 are formed, and wedges 120 andcenter section 150 removed, flashing 140 is removed (such as by trimmingwith fine scissors or diagonal cutters), leaving the desired skeletaltwo-dimensional filter frame/pattern 115, shown in FIG. 1C.

Skeletal frame 115 includes attachment struts 155 with proximal ends 165that are to be fixed or attached to proximal connecting member 170 ofFIG. 1D, adapted to cooperate with a guidewire (not shown). Attachmentstruts 155 extend seamlessly from support struts 156 because they areformed from the same precursor material. Support struts 156 areseamlessly connected to or seamlessly interconnected with one another.Seamlessly interconnected support struts 156 define a boundary,perimeter or cell having the configuration of a six-pointed “star.” Whenframe 115 is converted into a three-dimensional configuration, theseamlessly associated/interconnected struts 156 typically form a“closed” support member 156A that circumscribes the longitudinal axis ofthe three-dimensional frame, thereby providing a radial or transversedimension to the three-dimensional frame. The boundary, perimeter, cellor support member 156A can be any geometric configuration so long as itprovides a radial dimension (transverse to the longitudinal axis) forthe frame. The support member circumscribes the longitudinal axis of theframe and may also be described as being ring-shaped. In addition toproviding the frame with a radial dimension, as shown in FIG. 1D, thesupport member 156A is typically the location for attaching the proximalopen end 161 of the filter 160. Thus the support member also functionsto maintain the proximal end of filter media 160 in the open operativeconfiguration. Filter media 160 may be formed from any suitablematerial, and also includes a closed distal end 162.

The planar, two-dimensional frame pattern of FIG. 1C is then annealed,normally by thermal annealing, into a three-dimensional configuration.The three-dimensional annealed frame configuration 175, may be furtherprocessed, as described hereinafter, to include a filter media resultingin filter 100 which includes the frame 175 and filter media 160, as inFIGS. 1D and 1E. For ease of consistency and brevity throughout theremainder of the application and without relinquishing equivalentsthereof, Nitinol is used as the filter frame material in each and everyembodiment shown and described hereinafter. However, as discussed above,other suitable materials, such as, titanium nickel alloys, shape memorymaterials, biocompatible metals, e.g., stainless steel, or plastic maybe used for the uni-body filter frame.

FIGS. 2A-2C through 11A-11C depict alternate filter frame patterns thatcan be formed following the procedures described with reference to FIGS.1A-1E. As a result, the various struts are seamlessly interconnectedsince they are formed from the same precursor material.

FIG. 2A illustrates a plan view of an alternate frame pattern 215 havinghoop shaped struts 256 connected to attachment struts 255. FIG. 2Billustrates the three dimensional filter frame 275 after annealing withproximal ends of the attachment struts 255 fixed to the proximalconnecting member 270 and struts 256 seamlessly connected to one anotherand forming a closed support member 256A. As with FIG. 1C, struts 255seamlessly extend from support member 256A. FIG. 2C illustrates a filter200 attached to a guidewire 280. The filter 200 includes thethree-dimensional frame 275 with a filter media 260 having a “butterfly”configuration. The configuration of filter media 260 can also bedescribed as substantially parabolic.

FIG. 3A illustrates an alternate two-dimensional (plan view) framepattern 315 having attachment struts 355, attachment strut proximal ends365, filter struts 385 which may also support optional filter media 360of FIG. 3D. Filter pattern 315 also includes support struts 356. Supportstruts 356 and filter struts 385, which are seamlessly associated withone another, cooperate to define cell 357, which is configured in theshape of a diamond. Struts 355, 356 and 385 are seamlessly associatedwith one another since they are formed from the same precursor material.Struts 356 define a boundary around six cells 357 and form a closedsupport member 356A for maintaining the three-dimensional filter of FIG.3C in an open, operative configuration. FIG. 3B illustratesthree-dimensional frame 375 that is obtained after the two dimensionalfilter frame pattern is annealed, with the proximal ends 365 of theattachment struts 355 fixed to proximal connecting member 370.

In the embodiment of FIG. 3B, the filter struts 385 allow the device tobe used as a filter, without the filter media shown in FIG. 3C. Whilethe filter pattern of FIG. 3B shows six filter struts 385, any number offilter struts or support struts can be used, including, but not limitedto 4, 5, 7, 8, 9, 10, 11, 12, etc. In addition, although FIG. 3A depictsthe filter frame 315 with diamond shaped cells/openings 357, cells 357can be of any geometrical shape or size, so long as the openings are ofsufficient size to permit blood flow and/or filtering. FIG. 3Cillustrates the annealed filter frame pattern of FIG. 3B with filtermedia 360 attached to a guidewire 380.

FIG. 4A illustrates a two-dimensional alternate seamless frame pattern415 having attachment struts 455, support struts 456, and filter/filtermedia support struts 485. The pattern is seamless because it is formedfrom the same precursor material. FIGS. 4B and 4C illustratethree-dimensional views of filter frame pattern 475 after annealing,with the proximal ends of the attachment struts 455 fixed to theproximal connecting member 470, support struts 456 forming supportmember 456A, and filter media support struts 485 extending in a distaldirection. FIG. 4C illustrates the annealed filter frame pattern 475 ofFIG. 4B with filter media 460 attached to a guidewire 480.

FIG. 5A illustrates the two-dimensional alternate seamless filterpattern 515 having attachment struts 555, support struts 556, filtermedia support members 590, and filter support struts 585. The pattern isseamless because it is formed from the same precursor material. FIGS. 5Band 5C illustrate three-dimensional views of the filter frame pattern515 of FIG. 5A after annealing, frame 575, with proximal ends of theattachment struts 555 fixed to the connecting member 570, support struts556 of FIG. 5A form closed support member 556A, and filter media supportstruts 585 extend distally away from the proximal connector 570. FIG. 5Cillustrates the annealed filter frame pattern 575 of FIG. 5B with filtermedia 560 attached to a guidewire 580.

FIG. 6A illustrates the two-dimensional alternate seamless filterpattern 615 having attachment struts 655, support struts 656 and filtersupport struts 685. The pattern is seamless because it is formed fromthe same precursor material. FIGS. 6B and 6C illustratethree-dimensional views of filter frame pattern 615 of FIG. 6A afterannealing, with the proximal ends of the attachment struts 655 fixed tothe connecting member 670, support struts 656 of FIG. 6A forming supportmember 656A and filter media support struts 685. FIG. 6C illustrates theannealed filter frame pattern 675 of FIG. 6B with filter media 660attached to a guidewire 680.

FIG. 7A illustrates a two-dimensional view of a seamless alternatefilter pattern 715 having attachment struts 755 and support memberstruts 756. The pattern is seamless because it is formed from the sameprecursor material, for supporting the open end of filter media 760 ofFIG. 7C. FIGS. 7B and 7C illustrate side views of the three-dimensionalfilter frame 775, after annealing, with the proximal ends of theattachment struts 755 fixed to the connecting member 770 and supportstruts 756 of FIG. 7A forming support member 756A. FIG. 7C illustratesthe annealed filter frame pattern of FIG. 7B with filter media 760attached to a guidewire 780. FIG. 7D illustrates the annealed framepattern having articulation segments 790 in the attachment struts 755.FIG. 7E illustrates an alternate design, wherein there are twolongitudinally spaced support members 756A seamlessly interconnected toone another by articulation segments 790, described in greater detailhereinafter.

FIG. 8A illustrates a two-dimensional view of an alternate spirallyconfigured filter pattern 815. FIGS. 8B and 8C illustratethree-dimensional views of the filter frame pattern 815 of FIG. 8A afterannealing, frame 875, with a proximal end of the frame 875 fixed to theconnecting member 870. FIG. 8C illustrates the annealed filter framepattern of FIG. 8B with filter media 860 attached to a guidewire 880. Inthe filter frame illustrated in FIG. 8B, one of the turns of thespirally shaped frame, which is not “closed,” forms the support memberthat provides radial dimension to the frame.

FIG. 9A illustrates a two-dimensional view of an alternate seamlessfilter pattern 915 having attachment struts 955 and filter media supportstruts 985. The pattern is seamless because it is formed from the sameprecursor material. FIGS. 9B and 9C illustrate three-dimensional viewsof the filter frame pattern after annealing, frame 975, with theproximal ends of the attachment struts 955 fixed to the proximalconnecting member 970. In this embodiment the filter media supportstruts 985 closest to the proximal connector also function as the closedsupport member described herein to provide the transverse dimension ofthe frame and support the proximal end of the filter 960. FIG. 9Cillustrates the annealed filter frame pattern 975 of FIG. 9B and filtermedia 960 attached to a guidewire 980.

FIG. 10A illustrates a two-dimensional view of an alternate seamlessfilter pattern 1015 having attachment struts 1055 and a central portionof the planar Nitinol precursor material 1010 rendered porous 1090.FIGS. 10B and 10C illustrate three-dimensional views of the filter framepattern 1015 of FIG. 10A after annealing, frame 1075, with the proximalends of the attachment struts 1055 fixed to the connecting member 1070,and the porous precursor material 1090 having pleats 1095. FIG. 10Cillustrates the annealed filter frame pattern 1075 of FIG. 10B attachedto a guidewire 1080. A separate filter media is not necessary in theembodiment illustrated in FIGS. 10A-10C because the porous precursorportion 1090 serves as the filter media.

FIG. 11A illustrates a two-dimensional view of an alternate seamlessfilter pattern 1115 having attachment and filter strut 1156 which willalso function as the closed support member 1156A shown in FIG. 11B.FIGS. 11B and 11C illustrate three-dimensional views of the filter framepattern 1115 of FIG. 11A after annealing, frame 1175, with the proximalend of the closed support member 1156A fixed to the connecting member1170. FIG. 11C illustrates the annealed filter frame pattern 1175 ofFIG. 11B with filter media 1160 attached to a guidewire 1180.

Although the above embodiments show a single support member 156A, 256A,356A, 456A, 556A, 656A, 756A, 956A, etc., it is clearly within the scopeof the invention to have a plurality of longitudinally spaced supportmembers, i.e., members that circumscribe the longitudinal axis of theframe, that are seamlessly interconnected with one another via struts orarticulation segments, as in FIG. 7E. Similarly other embodimentsdescribed hereinafter may also include a plurality of seamlesslyinterconnected support members where the mechanism for interconnectionincludes struts, and/or the articulation segments which are definedhereinafter. In addition, when there are more than two support membersconnected to one another, some or all may be interconnected with strutsand some or all may be interconnected via articulation segments. Thus,there could be a series of two, three, four or more members, and in thecase with at least three support members that circumscribe the pattern'slongitudinal axis, both struts and articulation segments can be used inan alternating pattern.

FIGS. 12A, 12B, 12C, 12D and 12E illustrate alternate configurations ofstent strut, and apex designs which allow for, accept and houseancillary components. FIG. 12A depicts a housing 1210, which could bemachined, stamped, lasered or etched into the stent frame. Housing 1210is then filled with a material 1250 such as gold or platinum-iridium (toprovide enhanced radio-opacity) or with a therapeutic agent such as adrug (to provide a prescribed biological response). FIG. 12B depictshousing 1210 located along the side of a strut. FIG. 12C depictsmultiple housings 1210 along a strut. FIG. 12D depicts multiple housings1210 located within the strut periphery. FIG. 12E depicts an alternateshape (arrowhead) housing 1210 (to be used as a radiopaque markerhousing) located within the strut periphery. It should be noted thatmultiple shapes and sizes of housings could be configured. Theradiopaque markers could be located in any strut or support member ofthe frame of the filter or the stent. Advantages of the application ofradio-opaque markers in the fashions shown are: 1) stent cross sectionthickness is not increased (lending to reduction in introductory deviceprofiles), 2) allows for precise and uniform spacing of markers, and 3)allows for a multitude of shapes (dots, arrows and other characters suchas letters or words) to be easily incorporated into the frame. Thehousings may also provide a cavity in which to insert and/or attachonboard electronics or sensors.

FIG. 13 illustrates an embolic filter assembly system 1300 that includesthree functionally distinct regions. Section 1300A includes a supportwire that terminates at its distal end in connecting member 1370. Thesupport wire may be the guidewire 1380 used to deliver a therapeuticdevice, e.g., a deployment catheter or angioplasty balloon. Section1300B is any one of the embolic filter devices described in FIGS. 1A-1Ethrough 11A-11C described herein, or another other device describedhereinafter. Section 1300C may include an atraumatic tip 1396 or othersuitable tip known to those skilled in the art having a proximal endfixed/attached/cooperating with distal connecting member.

FIG. 14A depicts the filter apparatus 1400 as deployed in a vessel 1420with tortuous anatomy. As shown, such a condition results in anon-linear apparatus deployment configuration. In order for filter frame1410 to maintain sufficient vessel wall apposition (which eliminatesperi-device channel formations), the tether elements 1430 must becapable of deforming and/or articulating.

FIG. 14B depicts the filter apparatus 1400 as deployed at a differentsite within the same vessel 1420 anatomy of FIG. 14A, once againdemonstrating the flexibility required of the deflecting andarticulating tether elements 1430. It is clear in this depiction thatthe guidewire 1440 does not necessarily follow the host vesselcenterline. This phenomenon, coupled with anatomical variances and therequirement of complete vessel wall apposition of the filter frame 1410makes the inclusion of articulating tether elements 1430 a benefit andnecessity for safe and confident embolic protection of downstreamvasculature.

FIG. 15 illustrates an arrangement to attach a filter media to any ofthe annealed filter frames described herein. The frame 1515, issandwiched between filter media portions 1560A and 1560B, which arerespectively sandwiched between cushion elements 1500C and 1500D, whichlayered assembly is located between heated top plate 1500A and heatedbase plate 1500B. Thus, resulting three-dimensional lamination of FIG.15 has a cross-sectional view that is substantially conical. Applicationof heat and pressure, via heated platens 1500A and 1500B, result in theintegral bonding of the filter media 1560A and 1560B, and the interposedframe 1515. The filter frame configuration via the lamination proceduredepicted in FIG. 15 results in a filter assembly configurationresembling a “butterfly net.”

FIG. 16 schematically shows an alternate procedure for attaching filtermedia to an annealed filter frame. In FIG. 16, an annealed filter frame1615 is sandwiched between adjacent laminae of inner filter media 1660Aand outer filter media 1660B. Heat and pressure are applied via upperand lower punch and die platens 1600A and 1600B. The application of heatand pressure results in an integral bonding of the filter media 1660Aand 1660B and interposed frame 1615. During the heating and pressurelamination process, a vacuum may be applied in the lower platen 1600Bthereby bonding the filter media and skeletal filter frame together. Thefilter media shown in FIG. 16 is normally interposed only within theimmediate vicinity of the filter frame 1615. Additionally, theapplication of the vacuum can be used to optimize the filter framegeometry. The method shown in FIG. 16 can produce a filter frameconfiguration that resembles a butterfly net, such as the one shown inthe device of FIGS. 7A-7C. This method can also be used to produce aframe-supported “filter-in-filter,” which is shown in further detail inFIG. 17, described below.

FIG. 17 shows an alternate embodiment of the present inventionincorporating a two stage “filter-in-filter” design. Thefilter-in-filter design will provide improved filtration efficiencies,such as allowing each filter lamina to have a different porosity byusing an inner filter media 1760A and an outer filter media 1760B.Alternatively, either filter media 1760A or 1760B can incorporate anintegral Nitinol frame as one of the filter members. Alternativelystill, both the inner and outer filter media 1760A and 1760B could be anintegral Nitinol filter frame. Use of an uni-body Nitinol frame, such asthose described herein, would provide additional structural benefits inthe completed filter frame apparatus.

FIGS. 18A, 18B, and 18C schematically illustrate an annealing method inwhich a planar, two-dimensional filter frame is converted into athree-dimensional configuration with the use of an appropriatefixturing/tooling device, e.g., a mandrel. Mandrel 1800A, shown in FIG.18A, is used to form the filter frame 1815 of FIG. 18B into the desiredshape. After cutting a flat metal sheet into the desired two dimensionalconfiguration, such as that described above, the proximal ends 1865 ofattachments struts 1855, i.e., the endpoints of the two-dimensionalfilter frame 1815, are collected at a point along the axis of radialsymmetry as shown in FIG. 18B. As depicted in FIG. 18C, the filter frame1815 is placed onto the fixturing device, which, in this case, is themandrel 1800A of FIG. 18A to impart a defined, three-dimensionalconfiguration, and the frame 1815 of FIG. 18B is annealed to preservethe desired configuration. After annealing, the three-dimensional filterframe 1875 can be elastically deformed into its original two-dimensionalshape where a filter media can be applied according to any of themethods described and illustrated herein. Following the attachment ofthe filter media, the three-dimensional filter configuration is readilyobtained.

FIGS. 19A, 19B, 19C and 19D illustrate an alternate filter configurationusing a “sombrero” shaped filter media 1960B with a supporting frame. Toform the sombrero frame and filter shown in FIG. 19D, a conical filter1960, as shown in FIG. 19A, has its closed distal end 1962 invertedtoward the open proximal end 1961 of the conical filter 1960, to form aconvex, hat-like base as shown in FIG. 19B. This inversion shortens thefilter length, but retains the original area of the filter element 1960.Next, the convexity is increased until the apex 1963 extends beyond theopen end 1961, as shown in FIG. 19C. The filter 1960 thus has beenshortened further, but the effective filter area still remains identicalto the original conical filter area. The sombrero filter 1960B isattached to frame 1975, FIG. 19D. The frame includes attachment strutsthat are fixed to a connecting member 1970, which in turn iscooperatively associated with a guidewire 1955. Compared to conventionalconical filter frame designs, the sombrero filter frame allows moresurface area per unit length, or, alternatively, reduces filter lengthwithout compromising filter surface area and deflection of the trappeddebris away from the vessel centerline. The desired sombrero filterframe configuration will also increase the reliable removal of entrappeddebris.

FIGS. 19E and 19F depict an alternate filter sack configuration, alsodesigned to collect and hold embolic debris away from the vesselcenterline. In this case, an asymmetric cone shaped filter media sack1990 is produced and attached to the filter frame 1960. Collected emboliwill tend to collect at the tip of the sack 1990 and are held offset inthe vessel, thus allowing relatively unperturbed flow at the vesselcenterline.

As shown in FIGS. 20A, 20B and 20C, a filter in accordance with thepresent invention can be used to deliver a pharmaceutical substance,anti-thrombotic agent, drug, etc., into the blood flow in a hostlumen/vessel by deploying the filter in a lumen/vessel of interest. InFIG. 20A, a filter device such as that described in FIG. 17 above, canbe loaded with a pharmacological agent in one or more different areasbefore delivery into the host. Thus, the drug can be loaded betweenlayers of the filter media. The drug 2098 may be retained within thezone/space/area between the inner filter media 2060A and outer filtermedia 2060B ready to be delivered to the host.

Instead of using the filter-in-filter design of FIG. 17, any of theother filter configurations described herein can be used by imbibing thedrug into the filter media itself. As shown in FIG. 20B, the drug 2098can be imbibed into the media 2060 itself.

FIG. 20C illustrates drug administration in the host by deploying thedrug delivering system of FIG. 20A or 20B in a host lumen/vessel so thatthe blood flows through the filter media to elute the pharmacologicalagent, e.g., drugs. This method of localized drug delivery is effectivefor eluting a pharmacological agent contained either between adjacentlayers of filter media or imbibed directly into the filter media. Fluidflow through the filter device of FIG. 20A or 20B, or any other filterconfiguration described herein containing pharmacological agentsprovides a mechanism of mass transfer to downstream perfusion beds. Thepharmacological agent could be pre-loaded into the filter or injectedpost deployment perhaps through an extension of the support/guidewire.

As shown in FIGS. 21A and 21B, occluding device 2175 can be formed as adetachable endoluminal filter frame that can be implanted in the host.The occluding device 2175 thus implanted can either be permanentlyimplanted or retrieved at a later point in time, such as is required invena cava filtering applications. As shown in FIG. 21A, blood flowthrough the host can be obstructed by the implantation of the filterframe apparatus 2100. The filter frame apparatus 2100, used as anindwelling or implantable occlusion device is shown in FIG. 21A. Asshown in FIG. 21B, a guidewire or support wire 2180 includes a distalend 2181 that may be detached from proximal connector 2170 that isconnected to the occluding device 2175 or filter frame apparatus 2100.The support wire 2180 is used to position or remove occluding device2175 or filter frame apparatus 2100 from a lumen in a host. Theguidewire tip 2181 may be of any design for detachment from orreattachment to proximal connector 2170. Thus, the guidewire 2180 canhave any capture capability, including screw threads, magnetic,ball-and-socket, male-female attachment, bayonet, or any type ofcoupling that will allow the guidewire 2180 to detach or reattach to theproximal connector 2170 for placement or movement therein.

FIGS. 22A and 22B illustrate the use of a filter (similar to the filters100 or 700, respectively shown in FIG. 1D or 7C) to remove flowobstructions or to function as a thrombectomy device to removeintraluminal thrombus, for example. FIG. 22A shows an obstruction at thelumen wall in a blood vessel of the host. Though commonly the lesionwill have formed in a restrictive manner, the lesion is shown in across-sectional area with an upper and a lower component, that hasnarrowed the effective diameter of the lumen. Filter 2200 includessharpened support members 2285 to enable the filter to be used as a typeof scraper. The frame 2275 shown herein includes a filter media 2260 asa “catch bag.” In FIG. 22B, the filter 2200 is pulled with sharpenedmembers 2285, effectively shearing the obstruction/lesion from thevessel wall of the host. As the lesion is sheared from the wall, shearedlesion parts are collected in the catch bag or filter media 2260. Inthis manner, the present filter frame can be used to remove lesions andcollect the debris dislodged into the blood stream, to lessen thepossibility of clotting downstream of the host vessel. This approach canlikewise be used to capture and remove foreign objects from bodilypassageways.

FIGS. 23A, 23B and 23C respectively illustrate the use of the inventivefilter as an anchoring guidewire to facilitate the retention of aguidewire position in tortuous vessels of the renal circulatory system,and in particular for branch lumens offset at angles of approximately90°. Using the inventive filter frame as an anchor avoids or minimizesdamage to the host vessel, and specifically avoids or minimizes damageto the endothelium of the host lumen/vessel. FIG. 23A shows a lesion2300A in a branch lumen/vessel 2300B associated with the renal anatomyof a host. In the non-limiting embodiment of FIGS. 23A-23C, the branchlumen 2300B includes an approximate 90° turn toward the existing anatomyshown. As illustrated in FIG. 23B a filter frame 2375 is positioned andanchored in a renal circulatory vessel 2300B to fix the position of thesupport wire 2380. A slight pressure is imposed on the support wire 2380and the approximate 90° turn is extended to more than 90° withoutdislodging or altering the position of the guidewire in relation to thehost anatomy as shown in FIG. 23B.

As shown in FIG. 23C, a therapeutic catheter 2300C can be inserted overthe support wire 2380 of the filter frame to perform the intervention.As a result, therapy devices can more easily negotiate a greater than90° bend as shown in FIGS. 23B and 23C. Such therapy devices include,but are not limited to balloons, stents, etc. A further useful aspect ofthis embodiment is that, during its use, a long “exchange length”guidewire is unnecessary. Since this device is capable of maintainingit's positioning after deployment, the necessity of “rapid exchange” or“monorail” catheters are obviated.

FIGS. 24A, 24B, 24C, 24D and 24E show a further embodiment of thepresent filter frame assembly, which is intended to function as animplantable endoprosthesis 2476. As shown in FIGS. 24A and 24B, theinitial seamless filter frame 2475 is formed from a loop-type frame 2415from the same precursor material. In FIG. 24C, the proximal end of anopen-ended “windsock” shaped graft component 2477 is attached to theloop of the filter frame 2475 to form an endoprosthesis 2476. In FIG.24D, the loop-type frame 2475 with the attached open-ended windsock isdeployed proximal to an aneurysmal defect, and the windsock shaped graftcomponent 2477 extends downstream of the frame, effectively excludingthe aneurysm 2400A. Thus, frame and the opened ended sock function as animplantable prosthetic vascular conduit where the filter frame 2475functions as an anchoring stent, and the open-ended sock functions as abiocompatible liner. This device, shown in FIG. 24E, may then beoptionally lined with a stent 2480. This embodiment finds use as a stentand graft combination where the stent element would be deployed proximalto the intended therapy site and the graft element would be configuredto be deployed by blood pressure.

FIGS. 25A-25H illustrate an exemplary delivery system for deploying thepresent filter frame 2575 or filter 2500 of the present invention. FIG.25A illustrates a frame 2575 or frame-filter 2500, such as frame 175 orframe-filter 100 of FIG. 1D or 1E, frame 375 or frame-filter 300 ofFIGS. 3B and 3C, or any of the other frame or frame-filter assemblyherein described, attached to a support or guidewire 2580 and positionedwithin a tubular delivery sheath 2500A of a delivery catheter. FIGS.25B-25D illustrates front views taken from sectional plane A-A of FIG.25A, but without the frame 2575 or frame-filter 2500. The section A-A1(FIG. 25B) illustrates a dual lumen extrusion catheter sheath. SectionA-A2 (FIG. 25C) illustrates a single lumen extrusion having anadditional covering formed from a shrink tube. Section A-A3 (FIG. 25D)illustrates a second lumen adhered to the inner diameter of the tubulardelivery sheath 2500A of FIG. 25A.

FIG. 25E-25H illustrate the perspective detail of external guidewire2580 loading of a catheter lumen. FIG. 25E is a front view of the FIG.25G. FIG. 25F illustrates the catheter having a longitudinally extendingindented channel, which, as seen in FIG. 25G is circumscribed by atubular section 2500C. The guidewire 2580 is inserted into thelongitudinally extending channel 2500B between the external wall of thecatheter and the tubular section 2500C. In use, a filter frame orfilter-frame construct is pre-loaded into the distal end of the sheathadjacent to an exterior wire guide channel. The exterior wire guide isadapted to receive a guidewire in a rapid exchange configuration,however, unlike the prior art, the filter frame and guidewire 2580 arecompletely segregated and no aperture exists.

FIGS. 26A, 26B, 26C, 26D and 26E illustrate a method of using a filterframe assembly 2600 in accordance with the present invention. In FIG.26A, a lumen/vessel 2600A of the host has a lesion 2600B. A guidewire2680 is deployed into the lumen/vessel 2600A past the target lesion2600B. Thereafter, guidewire 2680 is back-loaded into the deliverysystem 2600C, such as the one described in FIGS. 25B-25D, 25F-25G, orFIG. 27B. Then the delivery sheath 2600C is advanced across the targetlesion 2600B. The delivery sheath 2600C is withdrawn, thereby allowing aself-expanding filter 2600 to deploy. The self-expanding filter 2600 isnormally designed to deploy spontaneously after the delivery sheath2600C has been withdrawn in this manner. Thus, as shown in FIG. 26C, thefilter 2600 is deployed downstream of the lesion 2600B. A therapeuticcatheter 2600D, such as an angioplasty balloon, is routed over thesupport wire 2680 in FIG. 26D to treat target lesion 2600B. As alsoshown in FIG. 26D, when the therapy is performed, the filter 2600functions to capture any emboli dislodged or removed by the therapeuticcatheter 2600D. Thereafter, as illustrated in FIG. 26E, the filter 2600is removed via insertion of a tubular capturing catheter 2600E over thesupport wire and retraction of the filter 2600 into the capture catheter2600E is performed. This retraction can be performed by pulling thefilter 2600 partially back into the capture catheter lumen 2600E,effectively trapping the emboli 2600F. In this manner, the lesion isdissipated through a therapeutic catheter without the result of any ofthe dislodged emboli or debris dislodging into the host.

FIGS. 27A, 27B and 27C illustrate a lumen 2710 having an auxiliary,internally positioned channel 2720 for receiving a guidewire 2730. FIG.27A illustrates the tip of the sheath having an internally located,peripherally positioned auxiliary channel 2720 formed by “pinching” theend of the tube wall as shown in FIG. 27B. FIG. 27C shows the guidewire2730 inserted through into the slit opening in the side of the catheterand exiting the tip.

FIG. 28 illustrates the use of the inventive filter 2800, as a vena cavafilter. Since the inventive filters described herein may be readilydetachable, the filter 2800 can be readily detached from a deploymentguidewire.

FIG. 29A illustrates a planar two-dimensional seamless pattern, formedfrom metallic material, or any other suitable biocompatible material.FIG. 29B illustrates a three-dimensional stent member formed from theplanar two-dimensional pattern of FIG. 29A, for use as an intraluminalstent. When extremely thin wall sections are required, such as incoronary stents, it is appropriate to fabricate the device from a planarsheet of material. Planar material can be manufactured thinner thantubing due to the extra requirements of concentricity placed upon tubingstock. It should be noted that although only one design has beendepicted, a wide variety of patterns and cell geometries may be producedfrom planar material. The various cell geometries are defined by theinterconnected struts of the stent. In FIGS. 29A and 29B fourinterconnected struts 2910 define the four sided cell 2920. This planarmaterial may be metallic or polymeric or a combination thereof, and inany case, may also be porous. Once the flat pattern is fabricated, it isformed into a 3-D shape (in the depicted instance, an open mesh tube).The formed stent may be either plastically deformable (and thus madefrom a malleable starting material) or may be self-expanding, in whichcase a super-elastic, pseudo-elastic or shape memory material may beused. Subsequent processing such as thermal treatment, diametricreduction, de-burring and polishing may be incurred, depending upon thespecific stent design. It should be understood that multiple 3-D stent“units” could be manufactured in such a way and attached together toform a much longer device.

FIG. 30 depicts a view of a flat pattern of filter frame 3010A andintegral tether element 3010B geometry as it would be cut from a tube.This tube may be made of a shape memory alloy such as Nitinol. Cuttingcould be accomplished by a variety of methods including machining, lasercutting, stamping or etching.

FIG. 31 depicts the flat pattern geometry of FIG. 30 subsequent toforming and annealing at a larger, functional size. Upon annealing, thefilter frame 3010A resiliently maintains this larger diametrical profileand the at least one tether element 3010B extends seamlessly from it.

FIGS. 32A-32E depict alternate articulation segments formed as anintegral part of the tether element thereby forming different tetherelement geometries, which allow articulation of the tether elements3010B in relation to the filter frame 3010A. FIG. 32A depicts the tetherelement 3010B with an area of reduced strut width e.g. reducedcross-sectional area, to allow increased flexibility. FIG. 32B depictstether element 3010B with several individual areas of reduced strutwidth to allow increased flexibility. FIG. 32C depicts tether element3010B with a reduced width and formed “hinging” area to increaseflexibility. FIG. 32D depicts tether element 3010B with a reduced widthand several formed “hinging” areas to increase flexibility. FIG. 32Edepicts tether element 3010B divided in two for a portion of its length.This division effectively increases the tether element flexibility so asto allow articulation. The articulation segment of the tether element,therefore, is configured to enhance the flexibility of the filterapparatus (and thus, conformance to the host vessel wall) as well as tominimize inadvertent trauma translated to the host vessel wall bymovement or manipulation of the guidewire.

An articulation segment of the tether elements or struts is a desirablefeature in that it allows adequate vessel wall apposition of the filterframe when the filter device is deployed in a curved segment of anatomy.In a curved segment, the tether element articulates and deflects toadjust for a non-linear deployment situation (See FIG. 14). Thus, thefilter frame itself can maintain an uncompromised and fully deployedcondition. Likewise, because of its ability to attenuate longitudinaltranslation, the articulation segment provides a means of mitigatingtrauma of the host vessel wall due to guidewire manipulation. It shouldalso be noted that the required deflection and articulation of thetether elements could be bought about by metallurgical means ratherthan, or in combination with, geometrical means. For instance, thetether 3010B and frame 3010A elements of FIGS. 32A-E, although seamlessand integral, may be exposed to different thermal processing parameters(for example: through the use of fixturing to provide differential heatsink qualities), thus rendering the tether 3010B ductile and pliablewhile the frame 3010A maintains the stiffness required for adequatevessel wall apposition.

The articulation segments, though described with respect to the variousframe patterns can be incorporated into any of the endovascular devicesdescribed herein. An articulation segment is a localized region thatprovides enhanced longitudinal flexibility. A localized region may havea cross-sectional area that is the same as the remaining part a strut,but differs in geometry. Alternatively, the localized region could havethe same geometry but a different cross-sectional area, or both thecross-sectional area and geometry of the localized region differ fromthe remaining part of the strut. An endovascular stent can havearticulation segments in any of the interconnected struts of FIGS. 29Aand 29B.

EXAMPLES OF THE PRESENT INVENTION Example 1 Nitinol Sheet Filter Frameand Integral Tethers

A radially-symmetric geometrical pattern comprising interconnectedstruts forming closed polygonal shaped cells was chemically etched froma sheet of Nitinol (NiTi) to produce a skeletal filter frame. Theetching, preferably photoetching of Nitinol (Kemac Technologies,Irwindale, Calif.) is continued to achieve a desirable materialthickness, to optimize the moment of inertia of the struts and to polishthe surface finish.

This filter frame is then subjected to a thermal treatment to set thephase transition temperature of the NiTi to approximately 37° C. byheating the filter frame to a temperature of about 450° C. for about 10minutes in an air convection oven (Carbolite Corporation, Sheffield,England) followed by a rapid quench in ambient temperature water.

The NiTi filter frame was then laminated between two (2) layers of anadhesive-coated porous polymer. The layers were positioned with theadhesive sides facing toward each other, and facing toward the NiTi. Theadhesive was used to adhere the layers of film together as well as tothe NiTi wire framework. A sacrificial porous polymer cushion materialwas used on each side of the device during this lamination procedure toprovide compliance of the surface during compression. This complianceallows the earlier mentioned porous polymer membrane to conform to thewire shape. The composite sub-assembly which included cushion, porouspolymer/adhesive laminate, NiTi, adhesive/porous polymer laminate, andcushion layers was then compressed in a SST fixture and heat treated at320° C. for 45 minutes in an air convection oven (Grieve Oven, TheGrieve Corporation, Round Lake, Ill.).

Once the ‘sandwiched’ device was removed from the heat source andallowed to cool, the sacrificial cushion material was peeled away fromeach side of the device and the NiTi wires were disengaged from thefixture. A circular shape of approximately 0.625″ in diameter wastrimmed into the porous polymer using a 20-watt carbon dioxide laser.The remainder of porous polymer was trimmed from the wire frame by handand discarded.

Following the laser trimming operation (which can also be used to createthe necessary pores in the filter media), the radially-oriented arms(struts) of the device were folded up and back on themselves to achievea hollow, three dimensional, semi-conical shape. To maintain the devicein this configuration, the NiTi struts were inserted into a SST tube.This tube measured approximately 0.05″ in length×0.035″ outerdiameter×0.025″ inner diameter. This tube and indwelling NiTi wires werethen crimped to a 0.014″ diameter guidewire to provide a guidewire basedendoluminal embolic protection device. The device resembled a threedimensional “whisk” shape with a pleated porous polymer filter elementattached to it.

The resulting pleats are designed to increase filter media surface areaover the generally conical shapes found in the prior art. This increasein surface area also allows for a shorter filter length which enhancesdeliverability of the device by a) decreasing friction in the deliverycatheter and b) improving device overall flexibility.

Example 2 Nitinol Tube Filter Frame and Integral Tethers

A 1.3 mm Nitinol tube with a wall thickness of approx 0.1 mm (obtainedfrom Nitinol Devices and Components, Fremenot, Calif.) was laser cut(Laserage Technologies Inc, Waukegan, Ill.) to a single, undulating 6apex ring geometry with integral tethers. This frame was then lightlygrit blasted at 40 psi with 20 micron silicon carbide media in a gritblasting machine made by Comco Inc, Burbank, Calif. The ring withintegral tethers was then gently pushed up a tapered mandrel until itachieved a functional size of approx. 6 mm. The ring, tethers andmandrel were then subjected to a thermal treatment to set the phasetransition temperature of the NiTi to approximately 37° C. in an airconvection oven (Carbolite Corporation, Sheffield, England) One skilledin the art will realize that variances in the geometry, metallurgy,thickness and heat treating of the filter frame can all be varied tocreate alternate embodiments with varying desirable properties. The ringand tethers (now at functional size) were then lightly coated with anfluorinated ethylene propylene (FEP) powder (FEP 5101, available fromDupont Corp, Wilmington, Del.) by first stirring the powder in a kitchenblender (Hamilton Beach Blendmaster, Wal-Mart) after the power was mixedinto a “cloud”, the frame was hung into the blender for enough time forFEP to build up onto the surface of the ring. The frame, now coated withFEP powder was hung in an air convection oven (Grieve Oven, The GrieveCorporation, Round Lake, Ill.) set at 320° C. for approx. one minutefollowed by air cooling to room temp.

The NiTi frame was then set atop a filter sack and attached though theapplication of localized heat (the heat causing the FEP coating on thering to re-melt and flow onto the surface of the filter sack, thusproviding a biocompatible thermoplastic adhesive). The tether lines werethen routed through a gold tube (Johnson Matthey, San Diego, Calif.)radiopaque marker. The tethers were pulled until they began to applytension to the frame. A guidewire was then inserted into the gold band(from the opposite direction of the tether lines). The marker band wasthen crimped to secure the tethers and guidewire together. A smallamount of instant adhesive (Loctite 401, Loctite Corp, Rocky Hill,Conn.) was applied to create a smooth transition from the guidewire tothe OD of the gold band. One skilled in the art will realize thatattachment of the filter to the guidewire could be accomplished byadhesion, welding, soldering, brazing, a combination of these, or anumber of other methods.

Upon drying, this embodiment of the endoluminal embolic filter is readyfor testing.

Various illustrative examples of the invention have been described indetail. In addition, however, many modifications and changes can be madeto these examples without departing from the nature and spirit of theinvention.

1. A method of constructing a uni-body, self-expanding filter framecomprising: extracting a substantially two-dimensional filter framepattern from a flat sheet of material by cutting; configuring saidtwo-dimensional pattern into a uni-body and seamless three-dimensionalfilter frame configuration; and thermally annealing said uni-body andseamless three-dimensional filter frame configuration.
 2. The methodaccording to claim 1, wherein said pattern includes attachment struts,support struts and filter support struts.
 3. The method according toclaim 2, wherein said filter struts are adapted to incorporate aradio-opaque marker without adding thickness.
 4. The method according toclaim 1, wherein the two-dimensional filter frame has at least oneclosed cell, the at least one cell including an area that has acircumference defined by a seamlessly continuous ribbon or strut of thesame precursor material.
 5. The method according to claim 1, furthercomprising attaching a filter media to the filter frame before or afterannealing.
 6. The method according to claim 5, wherein the filter mediaincludes a pharmacological agent.
 7. The method of claim 5, wherein aportion of said frame is positioned and laminated between two portionsof media.
 8. The method according to claim 5, wherein said patternincludes attachment struts and support struts.
 9. The method accordingto claim 8, wherein said attachment struts have at least onearticulation region.
 10. The method of claim 8, wherein the precursormaterial is a shape memory alloy.
 11. A method of assembly a filtercomprising providing a conical filter element; providing a uni-bodythree-dimensional seamless filter frame; and laminating said filterelement and frame together.
 12. A method of constructing a uni-bodyframe comprising: extracting a substantially two-dimensional plasticallydeformable frame pattern from a flat sheet of plastically deformablematerial by cutting; configuring said two-dimensional pattern into auni-body and seamless, three-dimensional frame configuration; andthermally treating said uni-body and seamless three-dimensional frameconfiguration.
 13. The method according to claim 12, wherein saidpattern includes attachment struts and/or support struts.
 14. The methodaccording to claim 12, wherein said pattern includes attachment struts,and/or support struts and/or filter support struts.
 15. The methodaccording to claim 14, wherein any of said struts are adapted toincorporate a radio-opaque marker without adding thickness.
 16. A methodof constructing a uni-body, self-expanding frame comprising: extractinga substantially two-dimensional frame pattern from a flat sheet ofshape-memory alloy, self-expanding material by cutting; configuring saidtwo-dimensional pattern into a uni-body and seamless three-dimensionalframe configuration; and thermally annealing said uni-body and seamlessthree-dimensional frame configuration.
 17. The method according to claim16, wherein said pattern includes attachment struts and/or supportstruts.
 18. The method according to claim 16, wherein said patternincludes attachment struts and/or support struts and/or filter supportstruts.
 19. The method according to claim 18, wherein any of said strutsare adapted to incorporate a radio-opaque marker without addingthickness.